title: Evaluation of thermal, ultrasonic and alkali pretreatments on mixed-microalgal biomass to enhance anaerobic methane production.
abstract: Anaerobic digestion was regarded as one of the ways to recover energy from mixed-microalgae biomass in this study. After applying thermal-, ultrasonic-, and alkali-pretreatments to raw microalgae biomass to promote the digestion efficiency, a biochemical methane potential was investigated to evaluate the effectiveness of the pre-treatments for the purpose. As the pretreatment intensity increased, the solubilization of the mixed microalgae increased. However, the increased solubilization was not followed proportionally by the increased methane production. The highest methane productivity was achieved by the thermal-pretreatment at 120 °C (405 mL CH4/g-VS), which was 1.2 times higher than that of the non-pretreatment condition (336 mL CH4/g-VS). The net energy analysis revealed that only the pretreatment adjusted to pH 9 yielded a slightly higher energy gains (12.8 kJ/g-VS) than that of non-pretreatment condition (11.9 kJ/g-VS). These findings recommend direct supply of microalgae biomass for anaerobic digestion.
authors.affiliation: Department of Civil and Environmental Engineering, Graduate School of Engineering, Pusan National University, Busan 609-735, Republic of Korea.
authors.forename: Sunja
authors.initials: S
authors.lastname: Cho
authors.forename: Seonghwan
authors.initials: S
authors.lastname: Park
authors.forename: Jiyun
authors.initials: J
authors.lastname: Seon
authors.forename: Jaechul
authors.initials: J
authors.lastname: Yu
authors.forename: Taeho
authors.initials: T
authors.lastname: Lee
mesh_terms: D000468:Alkalies; D000693:Anaerobiosis; D001483:Base Sequence; D018533:Biomass; D017931:DNA Primers; D008697:Methane / Q000378:metabolism*; D058086:Microalgae / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D014465:Ultrasonics
chemical_list: D000468:Alkalies; D017931:DNA Primers; D008697:Methane
keywords: Anaerobic digestion; Methane production; Microalgal biomass; Net energy balance; Pretreatment method